This next section is on building the cabin top hatch

I decided to build my own cabin top hatch for Tumblehome Nina.  I could have save hours of work by buying one but enjoyed the process of designing and building my own.  The hatch consists of coamings that are about an inch proud of the cabin top  made from 3/8ths Meranti plywood.  They are shaped to follow the camber of the cabin top.  Crowning the top edge of the coamings is a horizontal layer of 1/4 inch ply by 3/4 inch wide and fit to be flush with the inside of the coamings.  The hatch top is fit to sit snugly on top of this layer of 1/4 inch ply.  Later a strip of weather stripping will be applied to the inside of the hatch cover to fit directly above the 1/4 inch ply.  This will elevate the hatch sides up off the cabin top to provide a drip edge.  I am satisfied that anything short of a direct hit by a fire hose will not cause a leak.

There is a recess inside the hatch for a screen panel.